Abstract: A wide spectrum of reactivity is shown by methyl chloromethylphosphinate. Thus, it reacts with methoxide ion, methylamine, and dimethylamine to produce derivatives of methylphosphonic acid. An addition occurs with ketene diethyl acetal in the presence of tertiary amine. With thiophenoxide a displacement of chloride occurs. Reaction with Grignard reagents yields tertiary phosphine oxides; studies with deuterated compounds ...